build: fix wakatime json import bug (#2050)

* build: fix vercel node version

* build: remove engine property

* fix: add json import workarround

This commit adds a workaround for importing the `languageColors` JSON
file. This needed to be done since Vercel uses v16.4, which does not
support JSON file importing without the `experimental-json-modules`
flag. See https://simonplend.com/import-json-in-es-modules/
for more information. The workaround can be found [here](https://stackoverflow.com/questions/66726365/how-should-i-import-json-in-node).

package.json

@@ -16,9 +16,6 @@
   },
   "author": "Anurag Hazra",
   "license": "MIT",
-  "engines": {
-    "node": ">=13"
-  },
   "devDependencies": {
     "@actions/core": "^1.2.4",
     "@actions/github": "^4.0.0",